236 DECOMPOSING BLOOD, ETC. 



turned out to be a good culture medium, and which permitted of 

 following several of the interesting phases of growth and change 

 without more than ordinary trouble. The temperature which for 

 one part of the day was at summer heat in my room, may have 

 had much to do with these changes. 



It would be impossible to say from whence the rods both of 

 equal width and whip shape, and the spirilla, were derived ; but, 

 from my examinations of the excrement of the duck a few years 

 since, I am strongly inclined to suppose they each were derived 

 from it as left in the entrails thrown into the pail of blood, which 

 itself, no doubt, was of a rather heterogeneous character. But 

 little attention was paid to any of the other organisms. I will not 

 attempt to classify either the rods or the spirillum, which might 

 be Spirillum imdula^ as this is found in putrefying ditch water. 

 The rods are larger than those of the hay bacillus, as found in 

 infusions of hay or grass, and none of the spores were found 

 growing like the spores of the hay bacillus. As to the more or 

 less whip-shaped rods, I can offer no suggestion. The food 

 material of both the duck and fowl partaking of both the animal 

 and vegetable kinds, it would be difficult to fix the source without 

 considerable trouble and favourable opportunity. Sufficient has, 

 however, I trust, been indicated to show that our knowledge of 

 these minute organisms is far from perfect, yet every fragment has 

 its value. It may, perhaps, be worth while to state that when 

 examining the long, largely-arched vibrios with well curved ends, 

 I was surprised to see one suddenly spring back like a well-bent 

 bow to instantly resume its place, as if in effort to free itself, 

 though it remained otherwise motionless. This occurred twice in 

 different individuals. 



All the photo-micrographs were taken with the same objective, 

 and the objects magnified 520 diameters, except that of No. 7, 

 Fig. 62, which was taken with the i/5th objective, and magni- 

 fied 200 diameters. 



